Originally Posted by
You want to go where?
Not sure why DCA would be reliable but IAD mixed. They both experience essentially the same weather conditions. IAD may be slightly more prone to snow, but it has much more space to deal with other weather problems than DCA. DCA also has much more traffic which would mean slowdowns require longer to 'clean up'. My own experiences put IAD fully in the reliable category.
Looking back now, I'll concede that DCA and IAD were never apples-to-apples for me. It was almost always a UX connection to/from somewhere else at IAD, whereas DCA was usually mainline US metal and not a connection. When things go slightly awry, the UX flights were probably impacted a lot more than US mainline. Plus if there was a 45-minute delay at DCA, I probably didn't care as much.
I don't use either of them much anymore. DCA maybe 4-6 times a year and IAD almost not at all.
Now I'm flying west more than east...using PHX a lot and find it quite reliable.